Note: Descriptions are shown in the official language in which they were submitted.
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Express Mail Label
No. IB357243381US
PM-1699
ELECTRICAL SMOKING ARTICLE
HAVING CONTINUOUS TOBACCO FLAVOR WEB
AND FLAVOR CASSETTE THEREFOR
Backctround of the Invention
This invention relates to electrical smoking
articles, and more particularly to electrical smoking
articles having a continuous web containing a tobacco
f lavor medium, as well as to a replaceable cassette
enclosing the continuous web.
One type of electrical smoking article is
disclosed in commonly-assigned U.S. Patents
Nos. 5,060,671 and 5,095,921.
In such
an electrical smoking article, a flavor portion of a
tobacco flavor medium, such as tobacco or tobacco-
derived substances, is heated electrically to release a
tobacco flavor substance. As the substance is heated,
a smoker at the mouth or downstream end of the device
draws air in and around the heating element by
inhaling, and thereby receives the tobacco flavor
substance.
The above-identified patents disclose a
number of possible heater configurations, many of which
are made from a carbon composite material formed into a
desired shape. For example, one configuration involves
a radial array of blades connected~in common at the
center and separately connectable at their outer edges
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to a source of electrical power. By depositing tobacco flavor medium on each
blade and heating the blades individually, one could provide a predetermined
number of discrete portions of tobacco flavor substance to the smoker. Other
configurations included various linear and tubular shapes, subdivided to
provide
a number of discrete heating areas: Alternatively, semiconductor heaters, such
as those described in copending, commonly-assigned United States patents
5,498,850 and 5,659,656 can be used. Additional heater configurations are also
disclosed in US 5,659,656, as well as in commonly-assigned United States
patent 5,505,214.
Other configurations have been proposed. For example, various arrays of
discrete fingers or blades of heater material can be provided, each blade
providing one puff. However, suitable heater materials, such as those
described
in said Patent No. 5,060,671, are generally not strong enough to be an-anged
in
such a blade configuration without threat of blade breakage.
As disclosed in said Patent No. 5,060,671, such heating elements are
preferably disposable and replaceable. Therefore, they should be relatively
inexpensive to produce. Further, there should be a way of easily applying
tobacco flavor medium to the heating elements so that each activation of a
heating element delivers one portion or "puff' of tobacco flavor substance to
the
smoker, while preventing reheating of any one portion of tobacco flavor
medium.
1
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In addition, the replaceable heater/flavor
units heretofore described contain a limited number of
individual charges of tobacco flavor medium, and thus
provide a limited number of portions or puffs of
tobacco flavor substance to the smoker. For example, a
heater/flavor of the type described above might provide
eight or ten puffs, to mimic a conventional cigarette.
That requires the smoker to continually change
heater/flavor units throughout a day of using the
electrical smoking article. Each time the
heater/flavor unit is changed, additional wearing of
the contacts on the permanent portion of the article
occurs. Also, each spent heater/flavor unit increases
the volume of material disposed of.
It would be desirable to be able to provide
an electrical smoking article in which the tobacco
flavor medium is contained in a substantially
continuous tobacco flavor web.
It would also be desirable to be able to
provide a replaceable flavor or heater/flavor unit for
such an electrical smoking article which can provide a
relatively large number of flavor portions, to reduce
the wear on the permanent portion of the article, to
reduce the volume of material disposed of, and to
increase the convenience for the smoker.
It would further be desirable to be able to
provide a replaceable flavor or heater/flavor unit for
such an electrical smoking article which can be
manufactured easily and at relatively low cost.
Summary of the invention
It is an object of this invention to provide
an electrical smoking article in which the tobacco
flavor medium is contained in a substantially
continuous tobacco flavor web.
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It is also an object of this invention to
provide a replaceable flavor or heater/flavor unit for
such an electrical smoking article which can provide a
relatively large number of flavor portions, to reduce
the wear on the permanent portion of the article, to
reduce the volume of material disposed of, and to
increase the convenience for the smoker.
It is a further object of this invention to
provide a replaceable flavor or heater/flavor unit for
such an electrical smoking article which can be
manufactured easily and at relatively low cost.
In accordance with this invention, there is
provided an electrical smoking article having a source
of electrical energy, an elongated web containing
tobacco flavor medium, electrical heating means for
heating tobacco flavor medium in thermal proximity
thereto, puff sensor means for determining when a
smoker puffs on the article, and control means
responsive to the puff sensor means for applying
electrical energy from the source of electrical energy
to the electrical heating means to generate a tobacco
flavor substance from the tobacco flavor medium for
delivery to the smoker. There is also provided a
flavor cassette including a housing and a substantially
non-combustible elongated tobacco flavor web within the
housing. The tobacco flavor web has tobacco flavor
medium therealong. The cassette further has means for
supporting a section of the tobacco flavor web in
thermal proximity to the electrical heating means, and
means for advancing the tobacco flavor web past the
supporting means for presenting the tobacco flavor
medium to the electrical heating means.
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Brief Description of the Drawings
The above and other objects and advantages of
the invention will be apparent upon consideration of
the following detailed description, taken in
conjunction with the accompanying drawings, in which
like reference characters refer to like parts
throughout, and in which:
FIG. 1 is an exploded perspective view of a
first preferred embodiment of an electrical smoking
article according to the present invention;
FIG. 2 is a cross-sectional view of the
permanent portion of the electrical smoking article of
FIG. 1, taken from line 2-2 of FIG. 1;
FIG. 3 is an elevational view of the flavor
cassette of the article of FIG. 1, taken from line 3-3
of FIG. l;
FIG. 4 is a cross-sectional view of the
flavor cassette of the article of FIG. 1, taken from
line 4-4 of FIG. 1;
FIG. 5 is a perspective view of the
electrical smoking article of FIGS. 1-4;
FIG. 6 is a cross-sectional view, similar to
FIG. 2, of the permanent portion of a second preferred
embodiment of an electrical smoking article according
to the present invention;
FIG. 7 is a cross-sectional view, similar to
FIG. 4, of the flavor cassette of the second preferred
embodiment of an electrical smoking article according
to the present invention;
FIG. 8 is a perspective view of a third
preferred embodiment of an electrical smoking article
according to the present invention;
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FIG. 9 is a cross-sectional view of the
permanent portion of the electrical smoking article of
FIG. 8, taken from line 9-9 of FIG. 8;
FIG. 10 is a cross-sectional view of the
permanent portion of the electrical smoking article of
FIGS. 8 and 9, taken from line 10-10 of FIG. 9;
FIG. l0A is an enlarged elevational view of
the heater assembly of the electrical smoking article
of FIGS. 8-10;
FIG. 10B is a side elevational view of the
heater assembly of FIG. 10A, taken from line lOB-108 of
FIG. 10A;
FIG. 11 is an elevational view of the flavor
cassette of the electrical smoking article of
FIGS. 8-10, taken from line li-11 of FIG. 8;
FIG. 12 is a perspective view of a fourth
preferred embodiment of an electrical smoking article
according to the present invention;
FIG. 13 is an exploded perspective view of
the electrical smoking article of FIG. 12;
FIG. 14 is a cross-sectional view of a flavor
cassette of the electrical smoking article of FIGS. 12
and 13, taken from line 14-14 of FIG. 13;
FIG. 15 is a perspective view of a fifth
embodiment of an electrical smoking article according
to the present invention;
FIG. 16 is a fragmentary cross-sectional view
of the electrical smoking article of FIG. 15, taken
from line 16-16 of FIG. 15;
3o FIG. 17 is a fragmentary cross-sectional view
of the electrical smoking article of FIGS. 15 and 16,
taken from line 17-17 of FIG. 15;
FIG. 18 is a cross-sectional view of a first
alternative embodiment of the electrical smoking
article of FIGS. 15-17;
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FIG. 19 is a cross-sectional view of a second
alternat ive embodiment of the electrical smoking
article of FIGS. 15-17;
FIG. 20 is a cross-sectional view of a third
alternat ive embodiment of the electrical smoking
article of FIGS. 15-17;
FIG. 21 is a plan view of a first preferred
embodime nt of a tobacco flavor web according to the
present invention;
FIG. 22 is a cross-sectional view of the
tobacco flavor web of FIG. 21, taken from line 22-22
of
FIG. 21;
FIG. 23 is a cross-sectional view, similar to
FIG. 22, of a first alternative embodiment of the
tobacco flavor web of FIGS. 21 and 22;
FIG. 24 is a cross-sectional view, similar to
FIG. 22, of a second alternative embodiment of the
tobacco flavor web of FIGS. 21 and 22;
FIG. 25 is a cross-sectional view, similar to
FIG. 22, of a third alternative embodiment of the
tobacco flavor web of FIGS. 21 and 22;
FIG. 26 is a cross-sectional view, similar to
FIG. 22, of a fourth alternative embodiment of the
tobacco flavor web of FIGS. 21 and 22;
FIG. 27 is a cross-sectional view, similar to
FIG. 22, of a fifth alternative embodiment of the
tobacco flavor web of FIGS. 21 and 22;
FIG. 28 is a partially fragmentary plan view
of a sixth
alternative
embodiment
of the
tobacco
flavor
web of
FIGS.
21 and
22; and
FIG. 29 is a plan view of a second preferred
embodime nt of a tobacco flavor web according to the
present invention.
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Detailed Description Of The Invention
I. Theorv of the Invention
The present invention provides an electrical smoking article for "all-day"
use, by providing a substantially continuous flavor web, preferably in a
cassette,
that holds a relatively large number of portions of tobacco flavor medium. As
a
result, the smoker need not change the cassette that frequently--e.g., not
more
than once per day which means, first, that use of the article is more
convenient
for the smoker; second, that there is less wear and tear on the interface
elements of the permanent portion of the article; and third, that there is
less
waste to be disposed of from spent cassettes.
These results are preferably achieved by providing the tobacco flavor
medium on a base web of a suitable material, which is preferably substantially
non-combustible, although a web made of tobacco sheet without a base web
can also be used. Suitable means is provided for advancing the web past a
heater. A preferred base web material is a carbon fiber mat, which may be
woven or non-woven, such as that described in commonly-assigned United
States patent 5,369,723. A more particularly preferred base web material would
be similar to that described in US 5,369,723 but would have all of its carbon
fibers oriented substantially parallel to the long dimension of the web, to
maximize tensile strength in that direction. In still another preferred
embodiment, the web could be made from the tobacco flavor medium
itself, preferably reinforced with carbon fibers, which most preferably
would be continuous. Such a continuous-fiber reinforced web could be
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g
produced by casting the web as a continuous tobacco
sheet using a papermaking-type process familiar to
those skilled in the making of reconstituted tobacco
products, with continuous carbon filaments laid down
over the surface on which the sheet is cast.
In addition, the tobacco flavor web, whether
or not including a base web, can be reinforced by
longitudinal strips of a reinforcing material over less
than the full width of the web. Suitable reinforcing
materials include paper, metallic foils, and foil/paper
laminates, as discussed in more detail below.
In a preferred embodiment, the flavor
cassette resembles a tape cassette of the type used in
microcassette tape recorders, with the web wound on a
supply reel and attached to a take-up reel which
rotates to advance the web as it is consumed. In one
version of this embodiment, a heater is mounted in the
cassette. For example, the heater may be mounted where
the pressure pad of a microcassette tape would
ordinarily be mounted. Electrical contacts on the
outside of the cassette would mate with contacts in the
permanent portion of the article to provide electrical
power to the heater. In another version of this
embodiment, the heater is mounted on the permanent
portion of the article, and the cassette has an opening
into which the heater protrudes in thermal proximity to
the web.
An airflow passage is preferably provided in
the cassette to allow air to be drawn past the heater.
More preferably, the cassette is provided with a
mouthpiece, for use by the smoker, that connects with
the passageway and protrudes from the article when the
cassette is inserted in the article. In one preferred
embodiment, the mouthpiece is retractable, so that the
cassette can be packaged and sold with the mouthpiece
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retracted. Most preferably, the mouthpiece, whether
retractable or not, contains a filter that is
preferably replaceable. An appropriate filter might be
a conventional cellulose acetate filter plug of the
type used in conventional cigarettes. The plug might
be wrapped in tipping paper to give a familiar and
pleasing appearance.
The web might carry a continuous layer of
tobacco flavor medium, in which case the advancing
means would preferably advance the web sufficiently far
between puffs that no portion of the tobacco flavor
medium that was previously heated is reheated. This
would be the case particularly where the web is a cast
tobacco sheet. Alternatively, the web might carry
individual portions of tobacco flavor medium spaced
sufficiently far apart to be thermally isolated from
one another, so that when one portion is heated,
adjacent portions are not heated, and as a result, no
portion is ever reheated when it is used. In this
alternative, the web should be advanced with sufficient
accuracy that each portion is in proper registry with
the heater when the heater is activated to generate
tobacco flavor substance from that portion.
The "permanent" portion of the article might
be the size and shape of a conventional cigarette pack,
with a cavity for receiving the flavor cassette.
Within the cavity would be the contacts described above
for powering the heater, as well as capstans for mating
with the hubs of the supply and take-up reels for
advancing the tobacco flavor web. When the flavor
cassette is in the cavity with its mouthpiece
protruding, the electrical smoking article might have
the familiar appearance of a conventional cigarette
pack with one cigarette protruding from an open corner.
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The cavity might be in the end of the permanent portion, and the cassette
could be slid into the cavity endwise, with appropriate provisions for
retracting
the capstans as the cassette is inserted, as would be well known to one of
ordinary skill in the art of cassette tape recorders. For example, the
cassette
could actuate a lever as it is inserted which moves the capstans aside, or
which
releases the capstans and allows them to be pushed aside. Alternatively, a
door
could be provided in the side of the permanent portion to allow the cassette
to
be loaded directly over the capstans in another arrangement familiar in
cassette
tape recorders.
It is also possible to provide a cassette in a configuration other than that
of a conventional microcassette. Similarly, it is possible to provide a single
reel
of tobacco flavor web. In such a case, after the web is advanced past the
heater, it could then exit the housing of the permanent portion to be torn off
and
discarded by the smoker, or it could be fed into a waste receptacle which
might
be periodically emptied by the smoker.
Also in the permanent portion would be the power source (e.g., a suitable
battery or batteries), control circuitry and puff sensor described U.S.
Patents
Nos. 5,060,671 and 5,095,921. More particularly preferred embodiments of
those components, for use in the article of the present invention, might be
those
of commonly-assigned United States patent 5,505,214.
The permanent portion could also contain a suitable motor for accurately
driving the capstans. Stepper motors, which can be accurately advanced in
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small increments, are well known for use in
applications requiring precision control of position,
such as for computer disk drive head positioning.
Alternatively, an ordinary DC motor with suitable
reduction gearing can be used. The control circuitry
described above would, in addition to firing the heater
on detection of a puff by the smoker, also send a
signal to the motor to advance the web after each
portion is heated in preparation for the next puff.
The web could instead be advanced on detection of a
puff, before heating, but that is less preferable
because the time needed to advance the web might result
in a delay in delivery of tobacco flavor substance that
would be unacceptable to the smoker. The control
circuitry preferably also detects when the flavor
cassette is spent, by, for example, sensing the
inability of the motor to advance the web further, and
also preferably indicates to the smoker through a
suitable display the number of portions remaining on
the web, or that the cassette is spent, as described in
said above-incorporated patents and applications.
Alternatively, the web might be advanced by a
mechanical linkage that is manually actuated by the
smoker. For example, a trigger could be provided that,
when fully depressed and released, advances the web a
precise distance.
The amount by which the web must be advanced
is a function of the thermal conductivity of the web
material. The higher the thermal conductivity of the
web, the more of adjacent areas of the web will be
heated each time the heater is activated. The web must
be advanced far enough that no portion of tobacco
flavor medium is reheated. Otherwise, off tastes might
result from the generation of undesired substances on
reheating of a portion that previously had been
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inadvertently heated. Preferably, therefore, depending on the heater
dimensions, the web must be advanced by between about 4 mm and about 10
mm, and that is the distance the advancing motor must advance. When
individual flavor portions are provided, the flavor portions must be spaced
far
enough apart so that they are thermally isolated from one another--i.e., so
that
when a particular portion is being heated, adjacent portions are not also
heated
inadvertently. The distance that the web must be advanced is then a function
of
the separation on the web between portions of tobacco flavor medium.
Preferably, therefore, each portion is separated from adjacent portions by
between about 1 mm and about 4 mm, and that is the distance the advancing
motor must advance.
When the web is advanced, care must be taken that the supply reel does
not free-wheel, which might result in too much web being fed, or in the web
having insufficient tension to make good thermal contact with the heater. To
prevent such free-wheeling, and assure good thermal contact, a brake of
suitable conventional construction can be supplied, acting on either the
supply
reel capstan, in which case the brake would be in the permanent portion of the
article, or on the supply reel itself, in which case the brake would be in the
cassette. If the brake is in the cassette, then it is replaced each time the
cassette is replaced, which lessens the probability of brake failure.
Preferably,
however, the brake should be in the permanent portion to avoid the cost and
complexity of providing a new brake mechanism in each cassette.
A suitable heater is preferably made from the carbonaceous material
described in US 5,505,214 or in commonly-assigned United States patent
5,353,813. In another preferred embodiment, a silicon semiconductor material,
such as that described in commonly-assigned United States patent 5,505,214
may be used for the heater. A more particularly preferred embodiment is a
serpentine-shaped metallic heater. Preferred heater materials are (1 ) an
alloy of
about 75°~ nickel, about 16°r6 chromium, about 4.5°~
aluminum, about 3% iron,
and traces of yttrium, such as that sold by Haynes International, of Kokomo,
Indiana, under the trademark HASTELLOY~ or the trademark HAYNES 214~,
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(2) an alloy of about 51 °r6 nickel, about 24°~ chromium, about
14°~ tungsten,
about 5% cobalt, about 3°~ iron, and about 2°~ molybdenum, such
as that sold
by Haynes International under the trademark HAYNES 230~, or (3) an alloy of
about 80°~ nickel and about 20% chromium, such as that sold by Driver-
Harris
Co., of Harrison, New Jersey, under the trademark NICHROME~.
Although some of these heater materials may be too brittle for use in a
blade heater arrangement of the type described above without risk of blade
breakage, a single heater of the type contemplated herein can be supported
sufficiently to substantially negate such risk. Most importantly, the heater
can be
supported at both ends, unlike a blade that is supported at only one end.
As an alternative to mounting the heater in the cassette, the heater could
be mounted in the permanent portion of the article, with a suitable structure
in
the cassette provided to insure good contact between the web and the heater.
This has the . . . . . . . . . . .
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advantage that the heater can be wired directly to the
power source, rather than connected by mating contacts
that may be subject to unnecessary contact resistance.
However, if a permanent heater is used, precautions
should preferably be taken to isolate the heater from
the tobacco flavor substance that is generated.
Otherwise, the heater may be subject over the lifetime
of the permanent portion of the article -- which could
be quite long if the power source is replaceable or
rechargeable -- to being fouled by the condensation of
tobacco flavor substance. The resultant coating of
tobacco flavor substance on the heater may reduce the
heat transfer ability of the heater, and may also give
rise to off tastes as the coating is reheated. In
contrast, if the heater is changed with the cassette,
those effects will be substantially avoided or reduced.
The heater should preferably reach a
temperature of between about 400°C and about 500°C.
All of the heater materials referred to above are
capable of reaching that temperature range. However,
care should be taken that the surrounding materials can
withstand those temperatures. The carbon fiber mat
referred to above can withstand those temperatures.
The material from which the housing of the cassette is
made, which is usually plastic, must also be selected
with those temperatures in mind, or suitable insulation
between the heater and the housing~must be provided.
Once the correct materials are chosen, the
cassette can be manufactured easily, at relatively low
cost, by well-known tape cassette manufacturing
techniques. Substantially all that is necessary is to
substitute the web material for conventional recording
tape, and the heater for the pressure pad. It may also
be desirable to adjust the web path to soften sharp
2'1.29591.
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turns which the tobacco flavor web might be too brittle
to make, especially after being heated.
II. Preferred Embodiments
A first embodiment of an electrical smoking
article according to the present invention is shown
partially schematically in FIGS. 1-5. Electrical
smoking article 10 includes permanent portion 11 and
flavor cassette 12. Permanent portion 11 has cavity 13
for accepting cassette 12. Permanent portion 11 also
has a battery or power source 20, control circuitry 21,
puff sensor 22, and motor 23, all as described above.
Within cavity 13, permanent portion 11 also has a pair
of contacts 24 (one is shown in FIG. 2, and the other
is in the opposite wall of cavity 13 that is cut away
in FIG. 2) for delivering power to the heater in
cassette 12, and a pair of capstans 25, such as
conventional tape drive capstans, one or both of which
are mechanically linked at 26 to motor 23. (If both
capstans 25 are linked to motor 23, then motor 23 can
serve as the brake referred to above.) As stated
above, a suitable mechanical arrangement can be
provided by one of ordinary skill in the art to allow
capstans 25 to retract as cassette 12 is inserted in
cavity 13, or a door (not shown) can be provided for
insertion of cassette 12.
Power source 20, circuitry 21, sensor 22,
motor 23 and contacts 24 are linked by suitable
conductors 27.
As described above, cassette 12 has
substantially the same outward appearance as an
conventional recording tape microcassette, having
supply reel 40 and take-up reel 41, each having a
conventional hub 42 for mating with capstans 25.
However, instead of recording tape, supply reel 40
2~.~~~~~..
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carries web 43 as described above, bearing portions 44
of tobacco flavor medium, past heater 45. Heater 45 is
supported at both ends by flanges 46 (one shown), one
on each of the large walls of cassette 12. Contacts 30
on the outside of cassette 12 mate with contacts 24 in
cavity 13.
Cassette 13 also has a mouthpiece 31
extending from one end. Preferably, mouthpiece 31 is
retractable, with rails 46 guiding it and preventing it
from being inserted so far into cassette 12 that it
cannot be extended. For ease of packaging and
shipment, cassette 13 is shipped with mouthpiece 31
retracted. Mouthpiece 31 also has filter 32, such as a
conventional cellulose acetate cigarette filter.
Mouthpiece 31 is in fluid communication with
airflow passage 47 in cassette 12. Airflow passage 47
is substantially isolated from the remainder of the
interior of cassette 12 by wall 48, except where
wall 48 is open over heater 45. When cassette 12 is
inserted into cavity 13, airflow openings 49
communicate between airflow passage 47 and puff
sensor 22, while airflow openings 400 communicate
between airflow passage 47 and air tube 28 which
connects to the outside air at screen 50.
Web 43 is maintained in suitable contact with
heater 45 by appropriate braking (as discussed above)
of supply reel 40, and by guide members 401 which
assure that the path of web 43 is such that it contacts
heater 45 at all times. Web 43 is loaded so that
portions 44 are on the side of web 43 facing away from
heater 45 and into passage 47.
When a smoker puffs on mouthpiece 31, puff
sensor 22 detects the puff and causes control
circuitry 21 to activate heater 45 for an appropriate
predetermined period of time, evolving tobacco flavor
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substance from one of flavor portions 44 into passage 47, where the smoker
draws it, along with outside air from tube 28, through filter 32 into the
smoker's
mouth. After heater 45 is de-energized at the end of the predetermined period,
control circuitry 21 activates motor 23 to advance web 43.
Article 10 may have suitable indicators (e.g., on portion 11 ) to inform the
smoker of the state of heater 45, of any lockout period that any be provided
between puffs, and of the number of portions 44 remaining (or the end of web
43 having been reached), all as described in the above-mentioned patents and
applications.
As stated above, cassette 12 can be loaded with a length of web 43
bearing a number of flavor portions 44 sufficient to provide a full day's use,
or
more. It is possible that filter 32 may become saturated or otherwise unusable
before all of portions 44 are consumed. Accordingly, filter 32 may be made
removable so that it can be replaced by the smoker more frequently than
cassette 12.
"Permanent" portion 11 can be reused until power source 20 is depleted,
and can then be discarded. Alternatively, power source 20 can be removable
and replaceable, or rechargeable (either in or out of the article), all as
described
in said above-mentioned patents, in which case portion 11 can be substantially
truly permanent.
A second preferred embodiment of the invention is partially depicted
in FIGS. 6 and 7, the remainder being identical to the embodiment of
FIGS. 1-5. In this embodiment, permanent portion 60 has power source
20, circuitry 21 and sensor 22, as well as air tube 28, as in the first
embodiment. However, cavity 61 differs from cavity 13 in that a
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heater 62 is mounted in the cavity. Preferably,
heater 62 is mounted on a spring 63 for good contact
with web 71 of cassette 70. Cavity 61 also has control
contact 64 for mating with control contact 72 of
cassette 70.
Cassette 70 has airflow passage 47 and
mouthpiece 31 with filter 32, as above. However, in
this embodiment, motor 73 is in the cassette, and is
controlled via mating control contacts 64, 72.
Further, wall 74 defining passage 47 differs from
wall 48, having two openings for the passage of web 71,
so that web 71 can be fed into passage 47 to contact
heater 62 and then fed back out of passage 47 to take-
up reel 41. Guide elements 75 provide the proper web
transport path, assuring good contact between heater 62
and web 43. Finally, in this embodiment web 71 is
loaded so that flavor portions 76 face inward, away
from external heater 62 and into passage 47.
The operation of the embodiment of FIGS. 6
and 7 is functionally the same as that of the
embodiment of FIGS. 1-5. In further embodiments (not
shown), the heater can be in the cavity as in the
second embodiment, while the motor is in the permanent
portion as in the first embodiment, or the motor can be
in the cassette as in the second embodiment, with the
heater also in the cassette as in the first embodiment.
A third preferred embodiment 80, shown in
FIGS. 8-11, differs mainly in the configuration of
cassette 110. Cassette 110 is even closer than
cassette 12 to a conventional recording tape cassette,
to which a mouthpiece extension 111 has been added. In
addition, a heater access port 112 has been cut in the
sides of cassette 110. Cavity 90 of article 80,
accessible under door 81 (shown in the closed
position), is shaped to accommodate modified
~1.2~ ill.
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cassette 110. Like articles 10 and 60, article 80 has
capstans 25 in cavity 90, as well as air passage 28 and
opening 50 to allow outside air to be drawn in.
Heater 91 of article 80 is a serpentine-
s shaped metallic heater made of any suitable conductor
of appropriate resistivity. A preferred material is
the nickel-chromium-aluminum-iron-yttrium alloy
described above and identified by the trademarks
HAYNES 214~ and HASTELLOY~. Tha other nickel-chromium-
based alloys referred to above and identified by the
trademarks Haynes 230~ and NICHROME~ may also be used.
In addition, platinum-rhodium alloys can also be used.
Wire leads 27 electrically connected to power
source 20 and control circuit 21 are attached,
preferably by laser welding; to respective ends 102,
103 of heater 91. Ends 102, 103 are affixed to an
insulating substrate 104 through which leads 27 pass,
with heater 91 substantially perpendicular to substrate
104. Substrate 104 is in turn affixed to a ceramic
support 105. Substrate 104 is preferably a
polyetheretherketone (PEEK) polymer such as that sold
by Imperial Chemical Industries, of Great Britain.
Ceramic support 105 is preferably made from zirconia,
alumina or titanium dioxide. Also affixed
perpendicularly to substrate 104 and support 105 is a
ceramic clamping block 92, preferably made from the
same material as support 105. Clamping block 92
supports heater 91 at the top and the bottom, but
central region 93 of clamping block 92 is preferably
depressed to minimize conductive heat loss to clamping
block 92. Preferably, the surface 106 of clamping
block 92 in region 93 is coated with a gold layer 107
to reflect heat radiated by heater 91 back toward
web 43.
21.29 i9~.
- 21 -
Opening 112 is positioned directly adjacent
the end of air passage 115 in mouthpiece extension 111,
allowing the smoker to draw the tobacco flavor
substance as soon as it is evolved at heater 91. A
filter plug 32 is replaceably inserted into mouthpiece
extension 111. Whereas in article 10 substantially all
of filter plug 32 fit inside mouthpiece 31, in
article 80 most of filter plug 32 is visible.
Accordingly, it may be desirable to wrap plug 32 in a
suitable tipping paper having a pleasing appearance,
such as the familiar "cork" tipping paper used on some
conventional cigarettes.
A port 116 in the side of mouthpiece
extension 111 communicates between passage 115 and
corresponding port 94 in the floor of cavity 90, which
in turn communicates with puff sensor 100 (similar to
puff sensor 22) under the floor of cavity 90.
Motor 101 (similar to motor 23) is also located under
the floor of cavity 90 for driving capstans 25 of
article 80.
Constricted tube 117, preferably having a
diameter between about 0.024 in. (about 0.609 mm) and
about 0.032 in. (about 0.813 mm), provides a pressure
drop or resistance-to-draw (RTD) far the smoker of
between about 10 inches (about 254 mm) of water and
about 0.4 inches (about 10 mm) of water, and preferably
between about 6 inches (about 153 mm) of water and
about 4 inches (about 100 mm) of water. Having tube
117 between heater 91 and port 116 allows the pressure
sensing function to be separated from the body of
cassette 110, and eliminates the need to seal the many
openings in cassette 117 to maintain an adequate
pressure drop.
A fourth illustrated preferred embodiment,
shown in FIGS. 12-14, has the shape of a conventional
~1.~~591.
- 22 -
cigarette, although it likely has a greater diameter
and a greater length. In this embodiment, article 120
has a permanent portion 130 and a flavor cassette 131.
Permanent portion 130 is a substantially hollow
cylinder, containing all the functional elements
contained in permanent portion 11, above, but packaged
into a cylindrical shape. Permanent portion 130 has a
cavity 132 for insertion of cassette 131, and an air
tube (not shown) similar to air tube 28, communicating
between the outside air at screen 134 and airflow
passage 47 of cassette 131 at openings 400 of
cassette 131. Cavity 132 is similar, except in shape,
to cavity 13, above, and similarly has contacts 24 (not
shown in FIGS. 12-14) for energizing a heater 140 in
cassette 131 via contacts 135 (one shown) on the
exterior of cassette 131, as well as capstans 25 (not
shown in FIGS. 12-14) for engaging hubs 133 of
cassette 131. Indeed, although illustrated as
cylindrical, both cassette 131 and cavity 132 could be
rectangular.
Cassette 131 includes a supply of web 43
bearing tobacco flavor medium as in cassette 12.
However, in order to accommodate a sufficient web
supply in the smaller package of cassette 131, the
reels of cassette 12 are replaced in cassette 131 by a
pair of elongated belts 141, 142, which allow the web
supply to be spread over the length of cassette 131
without unduly increasing the diameter of cassette 131.
One end of each of supply belt 141 and take-up belt 142
runs over a respective one of hubs 133, while the other
end of each of belts 141, 142 runs over a respective
one of rollers 143. Cassette 131 preferably also has a
preferably replaceable filter 31 in a mouthpiece 144.
As depicted, cassette 131 does not have room for
mouthpiece 144 to be retractable as is mouthpiece 31 of
~.?~2~~~1.
- 23 -
cassette 12; however, a retractable mouthpiece 144 may
be provided in a suitable cassette of a type similar to
cassette 131.
While in each of the four embodiments
described above the web is advanced electrically, it is
also possible for the web to be advanced by a manually-
actuated mechanical linkage. A fifth preferred
embodiment of the present invention, using such a
linkage, is shown in FIGS. 15-20.
Article 150 is similar in shape to
article 80, except that mouthpiece 151, into which
filter plug 32 can be inserted, is at the center of one
end rather than in a corner. A door 152 is provided
for loading tobacco flavor web 160. An advancing
lever 153 rides in a slot 154, and is biased (not
shown) to the position in which it is shown in
FIGS. 15-20.
When lever 153 is moved to the other end of
slot 154, web 160 is fed from reel 161 past heater 91
as follows. Web 160 feeds between guide 164 and
substantially square drive members 162, 163, and is
advanced by the counterclockwise (as seen in
FIGS. 15-20) rotation of members 162, 163 and the
clockwise rotation of roller 165. When members 162,
163 are in the positions shown, web 160 is in contact
with or very close to heater 91 for good thermal
transfer. However, when members 162, 163 are
rotated 45° from the positions shown, it can be seen
that corners 166, 167 will hold web 160 near the upper
trace 168 of guide 164, and away from heater 91. Thus,
as web 160 is advanced, it does not drag against
heater 91. This minimizes fouling of heater 91, and
also decreases the chances for accidental breakage of
web 160 that might occur if it rubbed against
212~5~1
- 24 -
heater 91, particularly after web 160 had been weakened
by heating.
The advancing of members 163, 164 and
roller 165 is achieved by the mechanism shown in
FIG. 17, which is actuated by lever 153. As lever 153
is depressed, it pushes arm 170 bearing pin 171 against
ratchet teeth 172 of gear 173, rotating gear 173
clockwise. Gear 173 causes gears 174, 175,
respectively journalled on common shafts with
members 163, 164, to rotate counterclockwise, thereby
rotating members 163, 164. At the same time, gear 175
causes gear 176 to rotate clockwise, thereby rotating
roller 165 clockwise. The gear ratios are set so that
members 163, 164 rotate exactly 90°, and the sizes of
members 163, 164 are selected so that a 90° rotation
advances web 160 the desired distance. When the cycle
is complete and lever 153 is released, it returns under
spring bias (not shown) to its original position. As
lever 153 returns to position, pin 171 rides back over
ratchet teeth 172 of gear 173 without causing rotation
of gear 173.
FTGS. 18-20 show three alternative
embodiments of article 150, all of which use the manual
advance system of FIGS. 15-17. In first alternative
embodiment 180, shown in FIG. 18, power supply and
control circuitry 155 is at the bottom of case 181.
Tobacco flavor web 160 is supplied on a supply reel 182
and is taken up by a take-up reel 183. The two
reels 182, 183 can be separate reels, or can be part of
a cassette 184. Suitable means (not shown) can be
provided to allow a smoker to thread web 160 around
elements 162, 163 and between those elements and
guide 164. Alternatively, and particularly if
cassette 184 is provided, elements 162, 163, 164 can be
provided as part of cassette 184, which would have
-- 2 5 _
openings (not shown) through which shafts in
article 180 would engage elements 162, 163, 164.
Reels 182, 183 (and possible elements 162, 163, 164)
would all be replaced together through door 152.
In the second alternative embodiment 190 of
article 150, web 160 is again provided on reel 182, but
there is no take-up reel. Instead, the spent end 191
of web 160 is guided to slot 192 in case 181, where it
exits. The protruding end 191 can then be torn off by
the smoker and discarded.
In the third alternative embodiment 200 of
article 150, web 160 is again provided on reel 182, and
again there is no take-up reel. Here, the spent
end 201 of web 160 is guided to receptacle 202 in
case 181, where it accumulates. Receptacle 202, which
rides on guide 203 (more than one guide 203 may be
provided), can be removed for emptying by the smoker
periodically using handle 204.
While in each of the illustrated embodiments
the power source is an internally-contained battery
(which may be replaceable or rechargeable), it may also
be a capacitor. In such a case, charging contents
would be provided on the surface of the article. Such
contacts would also be provided if the power source
were a rechargeable but non-removable battery.
Finally, the power source of the article could be a
connection for attaching to an external power supply.
That connection may include suitable rectification or
filtering means.
A first preferred embodiment of the flavor
web of the invention, in which the tobacco flavor
medium is disposed continuously along the web 210, is
shown in FIGS. 22-28. As shown in FIG. 22, the web 210
may be made of the tobacco flavor medium 220 itself,
formed into an elongated sheet form by methods that are
~~.2~ i~1
- 26 -
well known in, e.g., the manufacture of reconstituted
tobacco products. Such an alternative may be
sufficient in some applications, depending on the
configuration of the path the web takes through the
smoking article, and the amount of friction expected.
If the configuration is such that an unsupported web
may break, especially after heating when the web is
weakened, then an alternative like that shown in
FIG. 23 may be used. As shown in FIG. 23, web 230 is a
laminate of tobacco flavor medium 220 and a support
layer 231. Support layer 231 may be a woven or non°
woven carbon fiber mat as described above, for which
suitable carbon fibers might be one-inch-long chopped
carbon fibers available from Akzo Fortafil, Inc., of
Rockwood, Tennessee, a subsidiary of Akzo America,
Inc., of Chicago, Illinois, as FORTAFIL~ 3C. Layer 231
may also be any other suitable material (e. g., suitably
treated paper) that adds strength to layer 220 and can
withstand the temperatures to which layer 220 will be
heated without generating off tastes.
It may be found that additional support is
needed beyond that provided by support layer 231. As
shown in FIG. 24, web 240 further includes reinforcing
strip 241. Strip 241 may be paper, metallic foil, or
a foil/paper laminate, and is disposed over only a
portion of the edge of web 240 to avoid interfering
with heat transfer between the heater and the web. As
seen in FIG. 25, further support can be provided by a
second reinforcing strip 251 similar to strip 241. If
two reinforcing strips 241, 251 are used, web 250 might
have to be slightly wider in order to present a
sufficient unobstructed area 252 to the heater.
In another alternative, it may be found that
strip 241, or the combination of strips 241, 251 is
sufficient to support continuous tobacco flavor medium
CA 02129591 2004-O1-19
- 27 -
strip 220, and two such alternatives 260, 270 are shown in FIGS. 26 and 27.
As a final alternative 280 of the first embodiment of the flavor web,
continuous carbon fibers 281 can be embedded in layer 220 during its formation
in the manner described above. Suitable continuous carbon fibers might be type
IM6T"" carbon fibers from Hercules Corporation of Wilmington, Delaware.
A second embodiment 290 of a flavor web according to this invention is
shown in FIG. 29. In this embodiment, individual portions 291 of tobacco
flavor
medium 220 are deposited on a carrier web 292. Any of the alternative
structures shown in FIGS. 23-25 can be used in this embodiment. As set forth
above, this embodiment requires greater accuracy in web transport than the
first
embodiment, so that portions 291 are in registry with the heater. However,
depending on the relative heat conductivities of the various web materials,
both
embodiments must be advanced approximately the same distance between
puffs, as discussed above, to prevent reheating of tobacco flavor medium to
avoid generation of off tastes.
Thus it is seen that an electrical smoking article, and replaceable flavor or
heater/flavor unit therefor, which can provide a relatively large number of
flavor
portions, which reduces the wear on the permanent portion of the article,
which
reduces the volume of disposed of materials, and which increases the
convenience for the smoker, has been provided. A replaceable flavor or
heater/flavor unit for an electrical smoking article which can be manufactured
easily and at relatively low cost has also been provided, as has an article
incorporating such a unit. One skilled in the art will appreciate that the
present
- 2g -
invention can be practiced by other than the described
embodiments, which are presented for purposes of
illustration and not of limitation, and the present
invention is limited only by the claims which follow.
